Holes will be punched.
February 12, 2009 6:41 AM Subscribe
My RFID Metro Q fare pass (Houston, TX public transport) specifically instructs, "Please do not bend or punch holes in this card". I want to punch a hole in it anyway.
How can I figure out where exactly the chip is located so that I don't destroy it when I punch a hole in it? I suppose that it is an RFID mechanism because the card doesn't need to be swiped through a magnetic reader and doesn't have any visible stripes, it just gets tapped to a pad at the train station every time I ride. I am not sure how the cashier at my school reloads it.
It does have one tiny rectangle (approximately 5x4 mm) that is barely perceptibly raised from the surface. Can I assume that as long as I stay away from it, my card will retain its function?
It's the only way I won't lose it again; punching holes through my school ID & magnetic key to my lab and attaching them to a lanyard with my essential keys on it has been a lifesaver (yes, I am aware that I invalidated my driver's license, but I use it exclusively for identification anyway and I have a new, valid one in the car I occasionally drive--at least I don't have to get a new one every two months).
How can I figure out where exactly the chip is located so that I don't destroy it when I punch a hole in it? I suppose that it is an RFID mechanism because the card doesn't need to be swiped through a magnetic reader and doesn't have any visible stripes, it just gets tapped to a pad at the train station every time I ride. I am not sure how the cashier at my school reloads it.
It does have one tiny rectangle (approximately 5x4 mm) that is barely perceptibly raised from the surface. Can I assume that as long as I stay away from it, my card will retain its function?
It's the only way I won't lose it again; punching holes through my school ID & magnetic key to my lab and attaching them to a lanyard with my essential keys on it has been a lifesaver (yes, I am aware that I invalidated my driver's license, but I use it exclusively for identification anyway and I have a new, valid one in the car I occasionally drive--at least I don't have to get a new one every two months).
"I am not sure how the cashier at my school reloads it." Reminds me of the MIT kids that hacked the Boston subway. But now onto the point: RFID cards typically come with two parts; The circuit and the antenna. The antenna is typically coiled along the inside of the card, usually taking up as much surface area as possible.
As long as you don't puncture the chip/circuit or the antenna, there's no reason why it would stop working.
posted by CapitalWasteland at 6:53 AM on February 12, 2009
As long as you don't puncture the chip/circuit or the antenna, there's no reason why it would stop working.
posted by CapitalWasteland at 6:53 AM on February 12, 2009
I'm not a scientist but I think there is possibility more inside than just a chip. This video would seem to indicate that in at least some RFID cards there is an antenna. Of course in the same video, you can see that most of that stuff is contained on the periphery of the card, which may help your cause.
On preview: Beaten to the punch
posted by syntheticfaith at 6:53 AM on February 12, 2009
On preview: Beaten to the punch
posted by syntheticfaith at 6:53 AM on February 12, 2009
OK, this is pretty much what I was talking about. A clamp that hold the card without needing a hole.
posted by AwkwardPause at 6:58 AM on February 12, 2009 [1 favorite]
posted by AwkwardPause at 6:58 AM on February 12, 2009 [1 favorite]
I have one of those cards! I carry it around in a bifold id holder thing attached to my keychain. I really wouldn't punch a hole in it.
posted by Neofelis at 7:05 AM on February 12, 2009
posted by Neofelis at 7:05 AM on February 12, 2009
The antenna may very well cover a majority of the surface. Take a look, for example, at this photo. The raised area you can feel is probably only the chip portion. The antenna needs to be relatively large in comparison.
And in case you think "Hey, that photo makes the antenna look fairly small, take a look at this photo. In short, the antenna could be right near the card's edge.
At my workplace they issue plastic ID card holders to people who want to put their ID cards on lanyards
posted by Mike1024 at 7:24 AM on February 12, 2009
And in case you think "Hey, that photo makes the antenna look fairly small, take a look at this photo. In short, the antenna could be right near the card's edge.
At my workplace they issue plastic ID card holders to people who want to put their ID cards on lanyards
posted by Mike1024 at 7:24 AM on February 12, 2009
Most RFID cards have a loop antenna that runs near the circumference of the card, as seen here.
If you look carefully, you may be able to see where the loop is running and punch there. If you know the type of card (say prox HID or Mifare, as linked above), you will be able to find images of it on the internet and see where the wires run.
posted by fake at 7:26 AM on February 12, 2009
If you look carefully, you may be able to see where the loop is running and punch there. If you know the type of card (say prox HID or Mifare, as linked above), you will be able to find images of it on the internet and see where the wires run.
posted by fake at 7:26 AM on February 12, 2009
After it expires take it apart to find the location of the chip and antenna and then you will know how to punch a hole through next month's card.
posted by caddis at 8:28 AM on February 12, 2009
posted by caddis at 8:28 AM on February 12, 2009
Best answer: Houston Chronicle 11/17/06 sec B, pg. 1 names the vendor as ACS Transport Solutions, Inc.
ACS helpfully lists references and has a case study [PDF] on Houston's contactless terminal project. For confirmation, the picture at the bottom of page two has a photo of the Q Card. The case study says there's 500,000 Mifare 1 cards and 6 million Mifare UL cards.
The Chronicle article stated the city had ordered many more disposable cards than the Q cards so I think you have a Mifare 1 card. Here's an image of the antenna of that card. Note the tiny Texas logo on the card.
I strongly recommend you get a second card to test this on before doing it on your main card. Also be aware the hole can provide a snag point for anything inside any system that would need to pull the card into it. I gather that's not the idea with these though. It was a problem with mag cards.
posted by jwells at 8:56 AM on February 12, 2009
ACS helpfully lists references and has a case study [PDF] on Houston's contactless terminal project. For confirmation, the picture at the bottom of page two has a photo of the Q Card. The case study says there's 500,000 Mifare 1 cards and 6 million Mifare UL cards.
The Chronicle article stated the city had ordered many more disposable cards than the Q cards so I think you have a Mifare 1 card. Here's an image of the antenna of that card. Note the tiny Texas logo on the card.
I strongly recommend you get a second card to test this on before doing it on your main card. Also be aware the hole can provide a snag point for anything inside any system that would need to pull the card into it. I gather that's not the idea with these though. It was a problem with mag cards.
posted by jwells at 8:56 AM on February 12, 2009
I was at Notre Dame a couple summers ago for a week; we ate in the school food service and were issued mag-stripe cards.
At the Notre Dame school bookstore, I bought a lanyard thing that was a holder for these lunch cards. It was a plastic widget with a slot in it that the mag card friction-fit into.
If this card of yours is the same thickness as a credit card, maybe your school bookstore has something similar.
posted by chazlarson at 2:24 PM on February 12, 2009
At the Notre Dame school bookstore, I bought a lanyard thing that was a holder for these lunch cards. It was a plastic widget with a slot in it that the mag card friction-fit into.
If this card of yours is the same thickness as a credit card, maybe your school bookstore has something similar.
posted by chazlarson at 2:24 PM on February 12, 2009
Or, cut a small tab from sturdy plastic [like maybe a margarine lid], Gorilla Glue it to the card, then punch your hole in that.
posted by chazlarson at 2:28 PM on February 12, 2009 [1 favorite]
posted by chazlarson at 2:28 PM on February 12, 2009 [1 favorite]
This thread is closed to new comments.
posted by AwkwardPause at 6:53 AM on February 12, 2009 [1 favorite]